Because their surface layers are fragile, primers are usually applied on the surface of inorganic cement building materials such as concrete, mortar, slate and the like for the purpose of improving the surface reinforcement or adhesive strength to paints for surface finish and the like. Heretofore, solvent primer liquid formed by dissolving synthetic resin into organic solvent has been employed as such primers. However, the solvent primer liquid is easy to ignite because of its volatility and further it affects the human body when the fumes are breathed. Thus, the above solvent primer liquid has many problems from the viewpoints of safety, sanitation, and the like.
The present application has previously developed aqueous liquid for primers wherein water is medium and organic solvent is not employed as medium, and has already applied to the Japanese Patent Office (JPA 62-80694). And, also as a further developed version, he developed one liquid type primer, which is formed by copolymerizing dimethyl aminoalkylamide acrylate or epichlorohydrin adduct of dimethyl aminoalkylamide methacrylate as a function group and alkoxysilane element to be the aqueous resin superior in reinforcement effects of the surface layer of base materials by crosslinking irrespective of the alkaline degree of base materials and already filed an application.
Although the above aqueous liquid can form a coat superior in waterproof by crosslinking under both circumstances of acid and alkali, when the concentration of resin is raised, shelf stability deteriorates due to high viscosity. In addition, it has a defect that the permeability to inorganic building material, reinforcing ability to base materials and waterproof properties deteriorate due to a rise of viscosity.